economic comparison of electric fuels produced at ... economic comparison of electric fuels produced
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Economic comparison of electric fuels produced at
excellent locations for renewable energies:
A Scenario for 2035
Philipp Rungea,e, Christian Sölchb,e, Jakob Albertc,e, Peter Wasserscheidc,d,e,
Gregor Zöttlb,e, and Veronika Grimm*a,e
a Chair of Economic Theory, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Lange Gasse 20, D-90403
b Professorship of Industrial Organization and Energy Markets, Friedrich-Alexander-University Erlangen-Nürnberg (FAU),
Lange Gasse 20, D-90403 Nürnberg, Germany
c Institute of Chemical Reaction Engineering, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Egerlandstrasse
3, D-91058 Erlangen, Germany.
d Forschungszentrum Jülich GmbH, Helmholtz Institute Erlangen-Nürnberg for Renewable Energy (IEK-11), Egerlandstr.
3, D-91058 Erlangen, Germany.
e Energie Campus Nürnberg, Fürther Str. 250, D-90429 Nürnberg, Germany.
June 10, 2020
The use of electric fuels (e-fuels) enables CO2-neutral mobility and opens therefore an alternative to fossil-fuel-
fired engines or battery-powered electric motors. This paper compares the cost-effectiveness of Fischer-
Tropsch diesel, methanol, and hydrogen stored as cryogenic liquid (LH2) or in form of liquid organic hydrogen
carriers (LOHCs). The production cost of those fuels are to a large extent driven by the energy-intensive
electrolytic water splitting. The option of producing e-fuels in Germany competes with international locations
with excellent conditions for renewable energy harvesting and thus very low levelized cost of electricity. We
developed a mathematical model that covers the entire process chain. Starting with the production of the
required resources such as fresh water, hydrogen, carbon dioxide, carbon monoxide, electrical and thermal
energy, the subsequent chemical synthesis, the transport to filling stations in Germany and finally the energetic
utilization of the fuels in the vehicle. We found that the choice of production site can have a major impact on
the mobility cost using the respective fuels. Especially in case of diesel production, the levelized cost of
electricity driven by the full load hours of the applied renewable energy source have a huge impact. An LOHC-
based system is shown to be less dependent on the kind of electricity source compared to other technologies
due to its comparatively low electricity consumption and the low cost for the hydrogenation units. The length
of the transportation route and the price of the filling station infrastructure, on the other hand, clearly increase
mobility cost for LOHC and LH2.
Keywords: Electric fuels, Hydrogen Utilization, Hydrogen Import, LOHC, Mobility
The energy supply of most economies in 2019 is strongly dominated by fossil fuels. In order to
achieve the 2° target formulated in the Paris Climate Agreement, this share must be drastically
reduced . In many applications, fuel substitution by direct electrification is possible and
reasonable. Examples are the use of heat pumps to provide heating for buildings or battery-powered
mobility systems for individual transport in the short- and medium-haul segment .
In other sectors it is much more difficult to replace fossil fuels. Especially in some segments of the
mobility sector, liquid fuels have considerable advantages over batteries due to their high energy
density and simple re-fuelling systems. This applies in particular to aviation and shipping, but also
to non-electrified railway lines, trucks, building machines, mining machines and cars on long-haul
journeys [3–5]. The sustainable synthesis and use of these fuels can be an appropriate way to
defossilize the abovementioned applications. For this purpose, established fuels such as diesel,
kerosene or methane can be used, or new fuels, such as hydrogen, methanol, ammonia or dimethyl
ether may be established.
Synthetic fuels can be produced in a number of different ways . In this paper, we examine the
generation of synthetic fuels using hydrogen from electrolytic water splitting. The production of so-
called electrofuels, electric fuels or e-fuels is highly energy-intensive. Hence the electricity costs are
of considerable importance for the total costs of the fuels. It may therefore be an interesting option
to produce the fuels at locations where the the levelized cost of renewable electricity are particularly
low and high capacity utilization rates (CUP) are to be expected. The energy-dense fuels can then
be transported to the world's energy consumption centres at comparatively low costs. This paper
therefore compares different locations with regard to their suitability for low-cost e-fuel production
und transport to Germany and also distinguishes between four widely discussed e-fuel candidates.
Niermann et al.  and Reuß et al.  compare the transport cost for different e-fuel like compressed
or liquid hydrogen, N-ethylcarbazole, dibenzyltoluene, 1,2-dihydro-1,2-azaborine, formic acid,
methanol, naphthalene, toluene for different transport distances. Niermann et al. focus on the long-
distance transport via tanker or pipline and Reuß et al on the supply of hydrogen filling stations by
pipeline and truck. However, these studies do not cover hydrogen production or the energetic
utilisation of e-fuels. The influence of the production site for the water electrolysis and the
production of different fuels is analyzed in [9–11] for sites like Brazil, Morocco, Egypt, Somalia,
Iceland or the German Bight. In [12–17] fuel cost are calculated in specific case studies. For
example, in Heuser et al.  the LH2 transport from Patagonia to Japan is investigated, in Gulagi
et al.  the transport of liquid synthetic natural gas from Australia to East Asia or in Teichmann
 the hydrogen transport from Canada to Germany via liquid hydrogen or as carbazole LOHC
system. Timmerberg and Kaltschmitt  show the transport of H2 from North Africa to Europe via
An analysis of the energetic utilisation of different e-fuels in light duty vehicles is provided in Runge
et al.  or Bongartz et al. . In Bongartz et al. hydrogen production is not part of the study, but
the influences of hydrogen purchasing cost are varied in a sensitivity analysis. Runge et al., on the
other hand, focus on hydrogen production under the assumption of different electricity market
designs in Germany.
This paper reports a techno-economic investigation of the production of e-fuels in seven regions
worldwide, which are excellent for different kinds of renewable energies. The e-fuels examined are
diesel, methanol and hydrogen, whereby the latter is transported either bound to a dibenzyltoluene
(H0-DBT)/perhydrodibenzyltoluene (H18-DBT) Liquid Organic Hydrogen Carrier (LOHC) system
or as cryogenic liquid at -253°C. The economic comparison of the fuels is finally based on the
mobility cost. We define these as fuel costs incurred by a 100 km drive with a compact car. The
decision to evaluate mobility cost and not only e.g. the heating value based cost of fuels is motivated
by the fact that both, the filling station set-up and the propulsion system, differ drastically between
the technologies. In our opinion, a comparison of the e-fuels with each other is only valid if the
complete chain up to the power train is evaluated. The resulting mobility cost are only valid for the
compact car described. However, the relative performance is also meaningful for heavier cars, buses,
trucks or trains by scaling.
For the evaluation of the mobility cost we set up a mathematical model, which covers the complete
process chain, from the electricity generation in the different regions over the fuel production up to
the transport of the fuels to the filling stations in Germany and the energetic utilization in the car.
The result is a process design optimized for location and fuel, which provides information about the
best interplay of different technologies and applications.
The paper is organised as follows. Section 2 introduces the seven different production sites. Section
3 briefly explains all model relevant process steps and summarizes all necessary assumptions before
the mathematical model is schematically presented in Section 4. The results are finally shown and
interpreted in section 5.
2. Production sites
The production sites considered in this paper are primarily selected for their excellent conditions for
various renewable energies. At the same time, good access to the sea is necessary to transport the
fuels by tanker to the consumption centres in other parts of the world1. In arid areas access to the
sea is also needed to produce fresh water for electrolysis. In addition, a low population density and
thus low local energy demand is essential in order to produce surpluses for export. Regions where
there had been serious political unrest in the past were also excluded from this study. The selection
made considers the regions shown in Figure 1.